This invention relates to a signboard which may be used as a traffic signal, danger signal, bumper sticker, billboard and the like, wherein a readily visible message is conveyed by means of letters, figures, symbols, etc. More particularly, this invention concerns a signboard which has a surface of weatherproof elastic or flexible, macromolecular material and a backing layer of adhesive containing bituminous material, whereby the signboard may be readily attached and firmly stuck along a curved, plain, angular or gently uneven surface.
Conventional signs and billboards useful for traffic signals, advertisement and so forth are often made by coating iron plates with paint or by directly painting particular areas, such as posts, road or the like with guiding signs. In the case of a metal plate, the material cost is generally high and moreover, the metal sign must be attached to some sort of pole, which is particularly uneconomical with respect to the high cost labor involved, as well as the required accessories, such as metal bands, nuts and bolts and the jigs and the tools used by the worker. The worker's burden is substantial and there is danger of injury. In addition, these materials are susceptible to rust, particularly if damaged by surface scratching and peeling of paint. Therefore such signs must be replaced about every three to five years. Also, such signs can cause damage to a contacting object, such as a car and in certain circumstances pedestrians may be injured with a sharp projecting part of a sign or billboard. Due to conductivity, such signs and billboards are unsuitable for use in places where they may come in contact with electricity; this can happen for example, if the sign slips out of its specified position after it has been attached, due to the loosening of the nuts and bolts.
If the sign has an unusual shape, there are the added disadvantages of the requirement of a large storage space, as well as of transportation of bulky weight cargo, in a way which avoids scratching the coating.
In the particular situation where the sign is painted when in place, the cost is even higher, because operators must then work in the field, and, according to the traffic situation, it may be necessary to carry out the work within a short period of low traffic flow, at night, or to temporarily decrease, or shut off the traffic flow, which of course is highly inconvenient.
When the signal is provided with a luminous tape, the disadvantages include the very high expense of the tape and the labor involved.